This paper introduces the collection of papers on impacts of sea-level rise on a number of European countries, and presents some overarching conclusions.

This study comprises a first-order evaluation of the implications of accelerated sea-level rise and some other aspects of climate change for Turkey's coastal areas. Global sea-level rise during the 20th century has been estimated between 10 and 20 cm and similar changes appear to have occurred along Turkish coasts, although available data is poor. Coastal cities cover less than 5% of the total surface area of Turkey, but they have over 30 million inhabitants and are growing rapidly. The Marmara region around Istanbul has the highest population density of all regions. At the same time, more than 60% of the Turkish Gross National Product (GNP) is produced in the coastal strip from Tekirdag to Kocaeli (along the northern shoreline of the Marmara Sea). Analysis suggests that the effects of a 1-m rise in sea level could be significant and adaptation costs substantial. This preliminary assessment suggests a capital loss of about 6% of current GNP, whereas simple protection/adaptation could cost 10% of current GNP. Continued urbanisation and tourist development will further increase exposure to sea-level rise. Currently, the consequences of sealevel rise and climate change are ignored in coastal management, and although strengthening of coastal management mechanisms is required for a number of reasons, sea-level rise and climate change should be considered an important long-term issue. To assist this, detailed case studies are recommended around Turkey's diverse coast, starting with the strategically important Istanbul area.

The Croatian coastline is long compared with the total national surface area. The coastal zone is mainly karstic and steep, with only one large alluvial plain, and contains approximately one-quarter of the total Croatian population. It is an important area for the national economy, particularly tourism and Mediterranean-type agriculture. Sea-level measurements at four points on the east Adriatic coast over the last 40 years indicate differential sea-level trends: from a rise between 0.53 and 0.96 mm/y to a decrease between −0.50 and −0.82 mm/y, a range mainly due to local tectonic activity.

In this paper, the effects of assumed 20- and 86-cm sea-level rises on the coastal area are assessed by expert judgement. Coastal areas appear to have, in general, a low vulnerability to changes in sea level. However, some important sites, such as historical town centres, the alluvial plain of the Neretva River, and Vrana Lake on the island of Cres would be seriously endangered. Because of its great length, the entire Croatian coastline cannot be fully protected. Therefore, long-term national adaptation strategies to sea-level rise and plans of actions should be prepared and adopted, and monitoring of the consequences of sea-level rise and further research should be implemented.

SAZETAK: Hrvatska je obala veoma dugacka u usporedbi s ukupnom povrsinom zemlje. Obalno je podrucje uglavnom krsevito sa strmom obalom. Obalno podrucje, koje nastanjuje 23% ukupnog broja stanovnistva, je znacajno za nacionalno gospodarstvo, osobito za turizam i Mediteranski tip poljoprivrede. Mjerenja razine mora na cetiri lokacija na istocnoj Jadranskoj obali u posljednjih 40 godina pokazuju, kao rezultat lokalnih dizanja odnosno spustanje obale uslijed tektonskih poremecaja, porast razine izmedju 0.53 i 0.96 mm/godina, odnosno pad razine izmedju 0.50 i 0.82 mm/godina. Procjena utjecaja pretpostavljenog porasta razine mora od 20 i 86 cm na obalno podrucje nacinjena je metodom ekspertske procjene zbog nedostatka odgovarajucih kvantitativnih podataka. Procjenjeno je da u najvecem dijelu obala nije osjetljiva na pretpostavljene promjene. Medjutim, neka znacajna mjesta, kao sto su povijesna sredista nekih gradova, dolina rijeke Neretve i Vransko jezero na otoku Cresu, mogu biti ozbiljno ugrozena. Zbog velike duzine obalne linije sasvim je razumljivo, da se cjelokupna cjelupna linija ne moze u potpunosti zastititi. Stoga je nuzno pripremiti i prihvatiti nacionalnu strategiju za obranu od ocekivanog porasta razine mora te plan i program potrebnih aktivnosti koji treba ukljucivati pracenja utjecaja i istrazivanje na odabranim lokacijama.

A preliminary estimate of the implications of climatic change on the Ebro delta coast (Spanish Mediterranean) is presented based on an understanding of how climate and other changes will influence the different driving factors that control the interacting formation and reduction processes acting on this low-lying coast. The formation processes are primarily of riverine origin and concern the supply of sediment and freshwater. The reduction processes considered are primarily of marine origin and include increases in inundation/flooding, decreases in storm return periods, coastal erosion, salinity intrusion, and changes in wave climate (wave height, direction, and storminess). For the most part, climatologically induced changes affecting deltaic behaviour, i.e., those of marine origin, are most important for the Ebro delta because those of riverine origin will be significantly damped by river regulation works. Hence, formation processes are suppressed whereas reduction processes will be unaffected by management policies, unless they are related to the coastal zone. Because of its morphology, relative sea-level rise (RSLR) will become the most important climate-induced potential hazard for the Ebro delta. When considering RSLR-induced inundation of deltaic areas below a given level (e.g., 0.5 m), although the deltaic surface below the projected level could be relatively large, impacts will be modulated by the “protection” offered by an active coastal zone that is able to react to the RSLR. Another direct result of sea-level rise will be a decrease in the return periods of maximum water levels, which due to the surge climate of the area will be very significant. Finally, the estimated shoreline retreat due to the RSLR was small when compared to present evolution rates. However, they must be also considered because they will act as an additional background erosion rate along the entire coast.

The Portuguese coastline has a high diversity of coastal types, which will react differently to an accelerated sea-level rise. Estuaries and coastal lagoons will be most affected by a rising sea level. Amongst these, the Sado and Tagus estuaries and the Ria de Aveiro and the Ria Formosa coastal lagoons are probably the ones where socioeconomic impacts resulting from accelerated sea-level rise would be greatest. Sandy shores will face increased erosion. However, it is likely that at this type of coast other factors, such as sand deficiency caused by damming river basins, will continue to play a larger role in erosion than accelerated sea-level rise. Hard rocky coasts will be the least affected by accelerated sea-level rise. Specific adaptation policies for accelerated sea-level rise impacts do not presently exist in Portugal. However, existing laws can be used to prevent and/or reduce socioeconomic impacts if they are strictly applied. A strong commitment to coastal management by Portuguese authorities is therefore necessary in order to prevent and minimise future implications of accelerated sea-level rise.

Ireland, as an island, has a long (<7000 km), crenellate, and cliffed coastline. More than 50% of its population (ca. 5.4 million in 1998) live within 15 km of the coastline. But most of these people are concentrated in a few major urban centres. Effectively, large areas of the coast have a low-density population. These factors mean that Ireland is seen as having an overall low vulnerability to the impacts of sea-level rise. Even so, about 30% of its coastal wetlands could be lost given a 1-m sea-level-rise scenario. People's valuation and awareness of the coastal environment in Ireland has been limited for much of the 20th century by factors of history and emigration. Many coastal areas have remained relatively undeveloped since the 18th and 19th centuries. In the late 20th century, an island-wide awakening to the resource potential of coastal and marine environments began to change this former neglect. In the Republic of Ireland, the Department of the Marine and Natural Resources was set up in 1988, and a separate Marine Institute was added in 1991. These developments established the coastal zone as an important element in future national strategic planning. This article examines the physical components of coastal vulnerability throughout Ireland under sea-level rise and climate change, coupled with the influences of people at the coast. These factors are placed in the context of the development of coastal zone management in Ireland and its links to reducing vulnerability.

Large parts of the coasts of Great Britain (including England, Wales, and Scotland) already experience a number of problems, including sediment starvation and erosion, loss/degradation of coastal ecosystems, and significant exposure to coastal flooding. Sea-level rise and other potential climate change will exacerbate all of these issues. Coastal management is embracing sea-level rise and climate change as one of the long-term issues that must be addressed, while recent nonstatutory guidelines are encouraging decision makers and actors alike to promote integrated coastal-zone management. Hence, preparations for adaptation to sea-level rise are more advanced than in most European coastal countries. In England and Wales, it is recommended that new coastal defences consider an allowance for accelerated sea-level rise. Strategic shoreline management plans have also been prepared, which include proposals for managed retreat (termed managed realignment) in flood-prone areas with low levels of development, and allowing continued erosion of retreating cliffs. More strategic tools for coastal management are also being developed. Future needs include a better response to the uncertainties of climate change, better guidance on managing the interaction between river flooding and sea-level rise in coastal lowlands, regional analyses of changes in coastal ecosystem stocks, and flood management for London and the Thames River. Scotland requires more basic assessment to define the key issues and needs.

The Belgian coastal plain and the Schelde estuary are threatened by sea-level rise. While of great economic importance with a threatened population of some 0.8 million (of a total population of 10 million), assessments of these risks are limited. This article describes the physical characteristics of the coast and undertakes a qualitative interpretation of its vulnerability. Low-lying polders are the most vulnerable to sea-level rise where a major problem is water drainage during rainy periods; their varying vulnerability to sea-level rise and increase in rain intensity is assessed, including the relationship between drainage levels and saltwater seepage. Freshwater lenses developed within the dunes are also vulnerable to sea-level rise, leading to threats to drinking water supplies from saltwater intrusion. Belgian coastal defence structures and their effectiveness are discussed. Historical sea-level rise during the past century, wave and wind data, and the evolution of erosion and accretion along the coast are interpreted. For Antwerpen, a harbour city on the river Schelde, the effects of sea-level rise are far from clear. Included here are historical data on changes in tidal amplitude during the 20th century. Future research needs should focus on the quantitative interpretation of data to understand the effect of sea-level rise on beach erosion, flood risk, and fresh and salt groundwater distribution. Furthermore, a thorough socio-economic study should be undertaken to assess the vulnerability of the Belgian coast and the Schelde estuary.

Based on historical hindsight, this paper shows that sea-level rise has played a fundamental role in the development of the low-lying environment of the Netherlands. It was beneficial in morphological terms during the mid-Holocene, but from Roman times, it has been a threat to the coastal zone evolution and human habitation. Collective human response started to play a role in coastal evolution as early as the ninth century, while its influence started to become a major factor during the nineteenth and twentieth century.

Throughout its history, Dutch society has always been receptive to new technologies, approaches, and policies in its dealings with the many water-related challenges. The success of concerted human response explains why the water boards were successful as the first democratic institutions in the Netherlands. Development of technology and increasing financial means (the Dutch Golden Age) gave rise to increasingly viable flood abatement measures and reclamation projects, which took place on increasingly larger scales. This culminated in large-scale works such as the closure of the Zuiderzee and the Delta Project in the twentieth century. During this project, a turning point in thinking emerged; while flood protection remained a top priority, human interventions were considered in a broader, more holistic context with natural values being weighed against socioeconomic interests.

In the face of the challenges of the twenty-first century, policy and management approaches as well as science and technology approaches need to be adapted further in accordance to the principles of working with nature in a trans-disciplinary way. The success of this adaptation will to a large extent determine the viability of the Dutch society as a whole.

Germany's coast extends over 3700 km on both the North and Baltic Seas and is shared by five coastal states. Major seaport cities, Hamburg and Bremen, form two of these states, whereas rural areas and small and medium-size coastal towns comprise the other three coastal states. Along the coast large low-lying areas are already threatened by recurring storm flood events and erosion. Accelerated sea-level rise therefore exacerbates a high-risk situation. It is estimated that under a 1-m accelerated sea-level rise scenario the recurrence of devastating storm floods that presently have a probability of 1 in 100 will decrease to a 1 in 10 or even 1 in 1 probability. Vulnerability assessments have been carried out in Germany at three scales: (i) the national level, i.e., for all coastal areas lying below 5 m (Baltic Sea Coast) and 10 m (North Sea Coast), (ii) the regional level for the coastal state of Schleswig-Holstein, and (iii) the local level for selected communities within this state. When comparing findings from these analyses, the results show that the economic risks of flooding and erosion are highest when detailed studies covering the full range of infrastructure assets are used. However, the actual risk areas in detailed studies may be more confined when considering local topography and infrastructure such as road dams. Nationally, an accelerated sea-level rise of 1 m would put more than 300,000 people at risk in the coastal cities and communities, and economic values endangered by flooding and erosion would amount to more than 300 billion US$ (based on 1995 values). This is why German coastal states are following a strategy based on hard coastal protection measures against flooding, although authorities realize that maintaining and/or improving these defence structures might become rather costly in the long-term. Although additional investment in flood and erosion protection will be considerable (estimated at more than 500 million US$) this seems manageable for the national and regional economies. On the other hand, hard coastline defence and accelerated sea-level rise will increase “coastal squeeze” on the seaward side, endangering important coastal ecosystems such as tidal flats (Wadden Sea), saltmarshes, and dunes. Currently there is no strategy to remedy this increasing ecological vulnerability.

The Danish coastline has continually changed since the last ice age with relative subsidence in the south and uplift in the north. The result is a low-lying country with raised beaches and wide marine forelands in the north and an archipelago in the south. The coastline is relatively long (7400 km) for an area of 42,000 km². Eighty percent of the population of 5.33 million (1 January 2000) live in municipalities with a coastline. Vulnerable low-lying areas contain 60,000 to 70,000 properties. These areas are mainly raised sea floor, marshes, and reclaimed areas. On the basis of present vertical movements and projected global accelerated sea-level rise (ASLR) it is estimated that relative sea level will increase by 33–46 cm within the next 100 years—notably in the southwestern part of Denmark. Increased storm intensity may enhance the impacts of this change in water level.

Dikes protect about 1100 km of the coastline and hard structures about 700 km. Soft solutions, especially beach nourishment, are increasingly used. So far direct planning for sea-level rise above the current secular rise has been modest and purely qualitative. The same applies to most new and upgraded coastal infrastructure, where the approach has largely been a “wait and see” attitude. Economical evaluations have been either unofficial or absent.

More attention has been paid to the impacts on coastal ecosystems, especially saltmarshes and sand dunes. Here the choice of action will depend on attitudes to and weighing of economic, sociological, and biological interests and options. The general strategy appears to be toward the preservation of a natural coastline, if necessary at the cost of land loss.

In comparison with many other coastal countries, it appears that Norway—as a whole—will not be seriously affected by accelerated sea-level rise. Topographical and geomorphological features, including a generally steep coastline and resistant coasts, suggest a low physical susceptibility to accelerated sea-level rise. For example, the southeastern coastal zone is experiencing isostatic uplift and is less exposed to extreme storm events than the western coasts. Nevertheless, some specific areas of Norway are highly dependent upon economic activities related to the coastal zone, which implies that the socioeconomic impacts of accelerated sea-level rise in these areas may be significant. Of particular concern are the low-lying areas in the southwest, which are characterised by soft, erosive coasts. Along the western and northern coastlines, the extensive and well-developed infrastructure of roads, bridges, and ferries linking cities, towns, and villages is likely to be negatively affected by sea-level rise, particularly if this is concurrent with an increased risk and height of storm surges. The potential economic costs of rebuilding and relocating infrastructure and other capital assets in these regions may be considerable.

SAMMENDRAG: Sammenliknet med mange andre land, vil Norge trolig ikke bli alvorlig påvirket av havnivåstigning. Topografiske og geomorfologiske trekk, som en relativt bratt kystlinje og kysttyper som er motstandsdyktige mot erosjon, tilsier en lav sårbarhet fra naturens side. Kysten i sørøstre deler av landet vil neppe bli påvirket av havnivåstigning, på grunn av fortsatt landheving og mindre ekstreme værforhold. Enkelte områder på sørvestlandet er imidlertid lavtliggende og består av erosjon-sutsatte sedimenter. Det faktum at aktiviteter knyttet til havet og kysten som sådan er en viktig bærebjelke for en del kystbyer og-tettsteder, gir imidlertid grunn til å anta at havnivåstigning kan få økonomiske konsekvenser her. På Vestlandet og i Nord-Norge vil trolig deler av lavtliggende infrastruktur, som veier, broer og ferjeleier, være utsatt i forbindelse med en havnivåstigning, spesielt hvis denne sammenfaller med økt risiko og høyde av stormflo. De potensielle økonomiske kostnadene forbundet med å bygge om og flytte infrastruktur og andre konstruksjoner i disse regionene, kan bli betydelige.

Poland's approximate 500-km coastline predominantly comprises sandy, low-lying beaches and populated coastal lowlands. They are exposed to a range of threats from recently observed intensified climate changes and anticipated accelerated sea-level rise. Sediment starvation is already indicated by the growing necessity for dune and cliff protection that has been exacerbated by sea-level rise.

The current study is both a summary and extension of existing Polish studies, and analyses current and predicted influences of accelerated sea-level rise on the coast. First, the Polish coast was divided into three areas according to coastal and socioeconomic characteristics. Then, considering two scenarios of accelerated sea-level rise [(i) 30 cm/100 y and (ii) 100 cm/100 y], an analysis of the threats of land loss and flood risk was carried out, and economic and social costs and losses assessed. This analysis included two adaptation scenarios: retreat (do nothing) and full protection.

These analyses show that the greatest impacts of accelerated sea-level rise would occur in the far-eastern and western regions of the Polish coast with lesser impacts along the central region. Threatened areas include the conurbation of Gdansk, the Zulawy polders, and the low-lying areas around the Szczecin Lagoon and the Odra river mouth. Because both the Szczecin Lagoon region and the Vistula River delta are of key importance for the Polish economy and are densely populated, a carefully planned response is required to manage these threats.

STRESZORENIE: Polska, posiadaja c okolo 500 kilometrowej dlugości piaszczysty i na wielu odcinkach nisko poloz ony brzeg morski, w wyraźny sposob naraz ona jest na roz nego rodzaju zagroz enia wynikaja ce z nasilaja cych sie w ostatnich latach zmian klimatycznych oraz przyspieszonego wzrostu poziomu wody (ASLR) w morzu. Pojawiaja cy sie deficyt osadow wzmaga erozje linii brzegowej, wydm i klifow co przeklada sie na konieczność coraz szerszej ich ochrony.

Niniejsza praca stanowi zarowno podsumowanie, jak i rozszerzenie dokonanych w Polsce studiow i analiz dotycza cych obecnego i przewidywanego wplywu ASLR na brzeg. Dokonuja c podzialu calego polskiego wybrzez a na trzy podstawowe, maja ce geograficzne i socio-ekonomiczne uwarunkowania, obszary (AREA I, II, III) oraz przyjmuja c dwa roz ne scenariusze przyspieszonego wzrostu poziomu morza (ASLR1-30 cm/100 lat oraz ASLR2-100 cm/100 lat) i zwia zane z nimi warunki brzegowe przeprowadzono analize zagroz enterenow, ryzyka ich chwilowego lub cze sciowego zalewania, a takz e wynikaja cych z tego tytulu kosztow i strat zarowno materialnych, jak i spolecznych. Analizy te zostaly wykonane w ramach dwoch podstawowych scenariuszy adaptacji, tj. opcji cofania sie (odsta pienia od ochrony) oraz wariantu pelnej ochrony zagroz onego brzegu i sa siaduja cych z nim terenow la dowych.

Wykonane analizy wykazaly, iz najwie ksze zagroz enie utraty lub niszczenia terenow i zwia zane z tym koszty materialne i spoleczne wyste puje w dwoch rejonach polskiego wybrzez a. Pierwszy z nich znajduje sie we wschodniej cze sci polskiego wybrzez a i obejmuje gdanska aglomeracje oraz cze sc Z ulaw drugi natomiast zlokal-izowany jest na zachodnim krancu Polski, obejmuja c nisko poloz one tereny wokol Zalewu Szczecinskiego i w rejonie ujscia Odry. Z uwagi na duz e zagroz enie a jednoczesnie znaczna narodowa wartosc obu tych obszarow wymagaja one wzmoz onej uwagi i priorytetu w ochronie.

Estonia is a coastal country with a long coastline (3800 km) for which climate change and accelerated sea-level rise are key problems that need to be considered in any future impact assessment. Due to its flat, low-lying coastal zone, any rise in sea level places many coastal ecosystems and recreationally valuable sandy beaches at risk. Milder winters, combined with increased storminess and the absence of sea-ice cover, would exacerbate these impacts. However, isostatic uplift and the distance of coastal settlements from the present coastline could reduce these risks.

This paper presents the potential impact of a 1-m global sea-level rise by 2100 if no adaptation is undertaken. Seven representative study areas, characterising all shore types in Estonia, were selected for sea-level rise vulnerability and adaptation assessment. The diverse structure of Estonia's coasts, the rapidly migrating shorelines, and the abundance of small islands were found to complicate reliable predictions regarding climate warming and accelerated sea-level rise.

SISUTUTVUSTUS: Eesti on pika rannajoonega (3800 km) mereäärne maa. Seetõttu on võimalik meretaseme tõus üks võtmeküsimusi kliima muutuse mõju hindamisel Eesti jaoks. Kuna siinne rannik on valdavalt madal ja tasane, on paljud väärtuslikud rannikuökosüsteemid kliima muutuse ja meretaseme tõusu korral hävimisohus. Paljud kõrge rekreatiivse väärtusega liivarannad lakkaksid eksisteerimast. Kliima muutusega kaasnevate pehmete talvede, jääkatte puudumise ning sagedaste tormide koosmõju teravdaksid veelgi ülalmainitud protsesse. Ent isostaatiline maakerge ja rannikuäärsete asulate paiknemine tänapäeva rannajoonest eemal mõnevõrra leevendavad riski suurust. Käesolevas artiklis on esitatud analüüsi tulemused aastaks 2100 toimuva 1 meetrise globaalse meretaseme tõusu stsenaariumi järgi tingimusel, et mingeid kaitse- ega kohandamismeetmeid ei võeta eelnevalt tarvitusele. Meretaseme tõusuga kaasneva rannikualade haavatavuse ning selle tagajärgedele vastavate kaitse- ja kohandamismeetmete analüüsiks valiti seitse võtmeala, mis esindavad kõiki peamisi Eesti rannikutüüpe. Eesti rannikutüüpide vahel-dusrikkus, kiiresti muutuv rannajoon ning saarte rohkus teevad kliima soojenemise ning meretaseme tõusu võimalike tagajärgede ennustamise väga keerukaks.

Adaptation is defined as the planned or unplanned, reactive or anticipatory, successful or unsuccessful response of a system to a change in its environment. This paper examines the current status of adaptation to sea-level rise and climate change in the context of European coasts. Adaptation can greatly reduce the impact of sea-level rise (and other coastal changes), although it requires adjustment of coastal management policies to changing circumstances. Consequently, adaptation is a social, political, and economic process, rather than just a technical exercise, as it is often conceived. The Synthesis and Upscaling of sea-level Rise Vulnerability Assessment Studies project has shown that adaptation to sea-level rise is widely divergent among European countries. Crudely, four groups of countries were identified:

At the European Union level, while coastal management is a focus, this effort is mainly targeted at today's problems. Hence, this paper suggests the need for a concerted effort to address adaptation in coastal zones across Europe. Sharing of experience among countries would facilitate this process.

This study documents the evolution of the coastal site on which an ancient port fortress, Pelusium, was positioned in the NE corner of Egypt's Nile Delta. Focus is on the stratigraphy, petrology, and faunal assemblages of radiocarbon-dated core sections recovered at major ruins at the site. The late Holocene development of this margin surface is unusual in that it has been subject to important geologically recent uplift since the city's founding, in contrast to predominant subsidence and relative sea-level rise that characterize most of the delta margin west of Pelusium. Vertical tectonics resulted from displacement along the Pelusiac Line, a major structural feature several kilometers south of Pelusium. The geoarchaeological survey shows the was built with ready access to the Mediterranean, after tectonic uplift, from ∼1000 to 800 BC. It was then, when Egypt was subject to Assyrian control, that the margin evolved from an open shallow marine (prodelta, delta-front) setting to a coastal one.

The city's progressive decline was influenced by warfare with Persians and other invaders from the east, effects of plague, and diminished role of its commercial and trade activities following construction of Alexandria by the Greeks. However, Pelusium's eventual demise also resulted from natural factors, especially tectonically controlled motion of the lower delta plain. Vertical shifts around 800–850 AD and subsequent periods resulted in rapid coastal build-out north of Pelusium. This caused a cutoff of the city from the sea and the Nile's Pelusiac branch, the major navigational byway into the delta.

Pelusium, after approximately 800–850 AD, continued as a commercial center for an additional three to four centuries prior to its abandonment by the time of the Crusades. Submergence of the city on the delta margin by rise of relative sea level has been effectively counteracted by episodic fault-related uplift of this lower plain sector and continued subaerial exposure since Byzantine time.

Before its western sector was stranded and/or buried ca. 4.0–3.8 ka BP (3.9–3.7 ka ¹⁴C), the Mississippi–Alabama chain of regressive barrier islands extended well into present southeastern Louisiana. Westward-directed net littoral drift, ebb-deltas, and microtidal inlet bypassing were instrumental in the formation of elongated, narrow, sandy barrier platform sectors on which these islands, mostly of strandplain topography, have originally emerged. The development of sizable subtidal–intertidal berm basins, ringed by swash and foreshore berm ridges that emerged after storms, then filled by storm-mobilized sand, has aided posthurricane recovery. These processes are linked to discrete stages in aggradational barrier genesis. Increasingly frequent and destructive cyclones reduced island areas to laterally extensive subtidal barrier platform intervals. Enhanced overwash across lengthened platform sectors reduced drift volumes and consequently island progradation. Deepened ship channels facilitated sand loss from littoral drift to offshore seafloor areas. This and the apparent reduction in the longshore sand flux point to natural and human interference with the drift supply. Comparisons of charts, aerial photos, and satellite images provide a quantitative record for the dynamic changes that occurred. Abrupt widening of Petit Bois Pass in 1916 and periodic island diminution and attrition episodes during at least nine hurricanes since had a decisive impact on all the islands. Breaches across low-lying central and eastern (updrift) sectors contributed to long-term island reduction. Starting with Hurricane Betsy (1965), more frequent and destructive tropical cyclones resulted in accelerated island diminution. Damage from wind, salt toxicity, and overwash, combined with shore retreat, seriously impaired the vegetation of several islands in 2005. Because of extensive low and narrow island sectors, Ship and Petit Bois were the most vulnerable. Between 1848–49 and 2005, they suffered 66% and 52% area loss, respectively. Despite recurring but limited post-storm recovery, East Ship now may be approaching extinction. Despite its higher relict beach ridges, secondary dunes, and historically substantial downdrift progradation, even Horn Island has undergone considerable attrition (23%).

Analyses of hourly measurements of ocean wave heights along the U.S. East Coast, collected since the 1970s by three buoys of the National Data Buoy Center, document a progressive increase during the summer months when hurricanes are most important to wave generation. In contrast, the waves measured during the winter, generated by extratropical storms, have not experienced a statistically significant change. Summer waves with significant wave heights greater than 3 m, which can be directly attributed to specific hurricanes, have increased at a rate of 0.059 m/y (1.8 m in 30 years) according to records from buoy 41002 offshore from Charleston, South Carolina, with a lower rate of 0.024 m/y (0.7 m in 30 years) recorded by the Cape Hatteras buoy (41001); both trends are statistically significant at the 90% level. A still lower rate is found for the Cape May buoy (44004), 0.017 m/y, suggesting that there is a systematic latitude variation. Histograms of the ranges of significant wave heights measured during the hurricane season show that the most extreme occurrences during the 1996–2005 decade are both higher and more common than occurred 30 years ago, at the beginning of buoy measurements, having increased from about 7 m to higher than 10 m. The waves recorded by the buoys depend on the annual numbers of hurricanes that followed tracks northward into the central Atlantic, how close their tracks approached the buoys, and the intensities (categories) of those hurricanes. Examinations of the storms that have occurred since 1980 indicate that the primary explanation for the progressive increase in wave heights has been an intensification of the hurricanes, with increased numbers of storms a contributing factor.

The Coastal and Estuarine Storm Tide (CEST) model for the boundary-fitted curvilinear grid has been developed recently to simulate a hurricane-induced storm surge. A new wetting-drying algorithm was based on accumulated volume and was created for simulating overland flooding. To evaluate the capability of the CEST model, it was compared with the well-established storm surge model—Sea, Lake, and Overland Surge from Hurricane (SLOSH)—in model grid representation and surge inundation prediction. Two models were compared: first, by carrying out storm surge simulations for Hurricanes Andrew (1992), Hugo (1989), and Camille (1969) over SLOSH's coarse polar grids with cell sizes of 500–7000 m. Results show that the CEST model agreed better with field observations of storm surge flooding. The CEST model was further evaluated by applying it to a fine-resolution curvilinear grid, which has cell sizes of 100–200 m at the hurricane landfall area, along with a superior representation of coastal topography. Comparison of the model results with field-measured elevations of high water marks and the locations of debris lines indicated that the CEST model, with the use of a fine-resolution grid, greatly reduced the uncertainty in computing storm surge flooding.

St. Joseph Peninsula is located in Florida, along the northeast coast of the Gulf of Mexico. Natural residual thermoluminescence (NRTL) analysis of quartz grains extracted from sands at eight localities showed a gradual reduction in NRTL intensity from south to north, which is also the accepted direction of longshore transport. Differences in NRTL reduction were also noted between grain size fractions, indicating either differential response to light exposure during travel, or different amounts of exposure between grain sizes. Laboratory experiments using simulated sunlight exposure in air and seawater were combined with natural exposure experiments, wherein differences in residence time in the swash zone between grain size fractions were quantified. In this study, sediment residence times in the swash zone along the St. Joseph Peninsula were estimated to vary from ∼25 days to ∼9 days depending on grain size. A 67% variance in littoral zone residence between 90–150-µm and 150–212-µm grains is revealed. The results of this study indicate the significance of NRTL as a novel method of sand transport analysis.

The goal of this study was to provide a comprehensive and updated inventory of the coastal caves of Puerto Rico in an effort to contribute to a better understanding of cave development in this island setting. A total of 63 coastal caves were surveyed and analyzed using detailed cartography, morphometric analysis, resource inventory, and photo documentation. Located along the northern, western, and southern coastlines of Puerto Rico, many of these features, because of their small size and relative obscurity, had not been thoroughly studied in the course of previous fieldwork. Prominent sea cave (littoral) development was noted in all coastal areas, but previously undocumented examples of flank margin speleogenesis were also identified within the Quaternary eolianite and adjacent limestone exposures along the northern coast. Morphometric analysis of all the completed cave maps revealed that the 10 flank margin caves could be graphically distinguished from the 53 sea caves by comparison of cave perimeter to total cave area. Furthermore, morphometric comparison of multiple spatial parameters was sufficient to differentiate intact from denuded flank margin caves as well as identify segments within some flank margin caves that had been modified by littoral breach and/or cliff retreat. This study revealed a surprising variety and abundance of cave resources along these dynamic and complex Atlantic and Caribbean shorelines, utilizing a methodology capable of differentiating between flank margin and littoral cave development that can be further used to determine the speleogenic origins of coastline cave resources in other carbonate island settings.

Linear and nonlinear wind-wave interactions are analyzed using wavelet linear coherence and wavelet bicoherence respectively. A selected record of simultaneously measured wind speed and wave height during a mistral event is divided into five segments, and the computations of the wavelet linear coherence and wavelet bicoherence are conducted for the whole record and for all divided segments.

In computing wavelet bicoherence, we consider both sum and difference rules of frequencies in order to have a complete picture of the phase coupling between wind speed and wave height. The results show that dividing the wind-wave record into segments gives the ability of exploring the detailed linear and nonlinear wind-wave interactions through the use of wavelet linear coherence and wavelet bicoherence.

Seagrass bed habitat is an important biotic community in decline worldwide. Boat damage has long been recognized for its negative impacts on shallow-water seagrass beds, with those along the Florida coast particularly vulnerable in the face of a large human population possessing a large number of boats. Boat scars to seagrass beds recover slowly, resulting in new damage that often outpaces recovery of existing damage. We examined the rate of accumulation of total area composed of boat scars from 1994 to 2005 at Lignumvitae Key Submerged Land Managed Area, an area containing approximately 3400 ha of seagrass beds. We found the total area of damage increased from 1994 to 1997 by an average of 27.1 ha/y and from 1997 to 2005 by an average of 10.8 ha/y. This most recent rate of damage increase represents an additional $1,523,819 annual loss in habitat value using cost figures based on costs from restoration attempts permitted by the Environmental Protection Agency. Severe groundings investigated by law enforcement officers showed increasing trends over time in the average amount and severity of damage. The size of the boat inflicting the damage was more closely related to the severity of damage than to the amount of damage. The most immediate and practical measures for preventing damage include increasing signage to warn boaters to avoid seagrass beds and increasing law enforcement staff. Signage is a relatively low-cost, long-term investment that becomes cost-effective even if only 0.03 ha of seagrass bed damage is averted over the life of the signs. Each patrol staff member added becomes cost-effective even if only 0.42 ha of damage is averted annually. Holding the total area of damage constant for 1 year (new damage = recovery) would represent a benefit–cost ratio of 25.71 if accomplished with only one additional law enforcement officer.

An accumulation rate in a well-developed mangrove forest has been associated with relative sea-level rise on an island off the coast of Rio de Janeiro State. This rate was calculated by ²¹⁰Pb dating models from a single sediment core. Results indicate an accumulation rate of approximately 1.7 mm/y for the past approximately 100 years. This rate is almost identical to the ongoing eustatic mean rise in global sea level, indicating a tectonically stable mangrove habitat. Organic C (OC), total N, δ¹³C_(OC), and δ¹⁵N values from selected core intervals suggest a constant source of accumulating vegetal debris, dominated by C3-type vegetation with insignificant input of marine-derived organic matter, and a stable subaerial mangal habitat.